Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/2tb55dd. Peter Todd answers the questions: why use Bitcoin over other blockchains, what are safe, future proof ways to peg data to Bitcoin's blockchain and what is Bitcoin script, and how it can be used. Filmed at qconlondon.com. Peter Todd is an independent applied cryptography consultant known for his research and educational work on better understanding and making use of "blockchain" technology, with a particular focus on scalability. He's also a long time contribution to Bitcoin Core, as well as maintainer of the python-bitcoinlib and OpenTimestamps projects.

1. Building On Bitcoin
Peter Todd
Mar 8th 2017
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Peter Todd QCon London

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blockchain-bitcoin
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4. What are we accomplishing?
Most software development makes things possible.
But security is about making things impossible.
Peter Todd QCon London

5. What kind of work are we doing?
”Blockchain” apps are cryptographic protocols.
Peter Todd QCon London

6. What is ”blockchain” cryptography?
”Blockchain” cryptography proves things.
Peter Todd QCon London

7. Timestamps
What is proven: Message m existed before time t.
How: OpenTimestamps
Peter Todd QCon London

8. Uniqueness
What is proven: Key k is maps to value v globally.
How: Transaction Outputs (Single-Use-Seals)
Peter Todd QCon London

9. Proof-of-Publication
What is proven: Message m reached a large
audience.
How: Hash-Lock Scripts
Peter Todd QCon London

10. Proof-of-Burn
What is proven: Thing x cost v to create.
How: Bitcoin Sacrifices
Peter Todd QCon London

11. Why use Bitcoin?
Stability
Peter Todd QCon London

12. Why use Bitcoin?
Proof-of-Work
Peter Todd QCon London

13. Thank you!
Peter Todd QCon London

14. Watch the video with slide
synchronization on InfoQ.com!
https://www.infoq.com/presentations/
blockchain-bitcoin